As Britain’s tabloids close ranks in condemning the publication of pictures of a sunbathing Duchess of Cambridge, it is tempting to conclude that a fear of Leveson lies behind the outbreak of criticism. But in truth anybody who has followed the history of celebrity holiday pictures will know the tabloids are far more cautious than they used to be, after a series of PR disasters and adverse legal rulings have forced privacy issues up the agenda.

It was the Sun that in 1999 published a “saucy, but harmless” picture of Sophie Rhys-Jones on its front page under the unambiguous headline ‘Sophie Topless’, only to print a lengthy and grovelling apology the next day.

Two years later, the People, then edited by Neil Wallis, published pictures of ‘DJ Sara Cox in the Nude!’ and what it described as “two of her greatest hits” – pictures taken without the consent of the BBC Radio 1 DJ when she was on honeymoon in the Seychelles.

Cox said the images “ruined all memories of my honeymoon for the rest of my life” and she received a landmark £30,000 payment following legal action. That ruling has largely set the tone since; in effect such explicit pictures are now banned by the British press. For example, a year or so before its closure, the News of the World considered whether to publish pictures of a topless Jennifer Anniston, but concluded after consulting with the Press Complaints Commission that it was not worth doing so because the images had clearly been taken without consent.

It is this notion of consent that lies at the heart of the thinking of tabloid editors and picture desks today: drawing a distinction between long-lens paparazzi pictures and those published every weekday at close range on page three of the Sun or the Daily Star.

At the same time, there is little economic or reputational advantage to publishing intrusive pictures in the hope of greater sales; today’s publishing model is better illustrated by the success of Mail Online – in an era of photographic plenty there are more than enough pictures tweeted by pseudo-celebrities in their bikinis or wardrobe malfunctions on red carpets to keep readers of the right column “sidebar of shame” clicking away.

Tabloid publishers, and those close to them, have preferred to emphasise that the Duchess pictures furore illustrates the complexity of attempting to regulate the press, because magazines and newspapers operating abroad went ahead and published the images, which were taken in the south of France.

But nobody expects that to weigh with Lord Justice Leveson, who is preparing his final report for David Cameron, and who has chosen to focus on the subjects of news stories, to redress grievance or inaccuracy and has little interest in getting involved with the intricacies of whether it is possible to restrain dissemination of controversial images online.

It will be of much greater concern to see that Ireland, whose system of press regulation had been held up as a model that Britain should follow, has threatened to abandon self-regulation in favour of a full-blown privacy law.

In France there is already such a law, but it did not act to restrain the Berlusconi family’s Closer. The magazine published the pictures of the duchess, taking the calculated risk that in doing so it would at worst escape with a manageable fine.

• This article was amended on 19 September 2012 to clarify that Sara Cox received a £30,000 payment from the People, not a £50,000 payment as originally stated